Unintentional weight loss in older adults.

Unintentional weight loss (i.e., more than 5% reduction between 6-12 months) in older adults of 65 years of age is associated with increased morbidity and mortality. The aetiologies that most appear in the third age are: malignancy and non-malignant diseases such as gastrointestinal disease and psychiatric disorders. In general, non malignant diseases are the most common causes of unintentional weight loss. The use of medications and polypharmacy can interfere with taste or cause nausea. This should not be overlooked when considering factors that contribute to unintentional weight loss in the elderly. Finally, certain social factors may also contribute to the involuntary loss of weight.

The evaluation of unintentional weight loss begins with a patient´s history. If there is a concern about cognitive impairment, caregiver or family members can provide corroborative information. The history should focus on the amount of weight lost and the time frame in which the weight loss occurred. Appetite evaluation will determine if weight loss is related to the consumption of nutrient-poor foods. It is important to review the diagnostic systems to detect the presence of an acute disease or the worsening of existing chronic diseases, paying special attention to cardiovascular, respiratory and gastrointestinal symptoms.

Recommended tests to detect this problem include: a complete blood count, a basal metabolic panel, liver function tests, thyroid function tests, C-reactive protein levels, erythrocyte sedimentation rate, glucose determination, lactate dehydrogenase detection and urine analysis. Thoracic radiographs and occulted blood in faeces tests should be performed. Abdominal ultrasound can also be considered. When the evaluation of these parameters doesn’t provide data to issue a diagnosis, an observation period of three to six months is recommended. As nutritional strategies, nutritional supplements and flavour enhancers, dietary modifications that take into account the patient’s preferences and chewing or swallowing disabilities should be considered. Appetite stimulants can help increasing weight, but they have serious adverse effects and no evidence of decreasing mortality.

The Mini-Nutritional Assessment is a validated tool to help measure the risk of malnutrition, accompanied by anthropometric measures and general dietary (such as the blood and urine tests indicated above) and subjective assessments. In this context, the score obtained in the Mini-Nutritional Assessment test is a very simple tool to evaluate the nutritional status in this population segment. The evaluation to detect depression and dementia is also instrumental, because both states have been shown to contribute to involuntary weight loss in older adults. Body weight should be evaluated without shoes with a clinical scale. The evaluation of the oral cavity and the dentition may indicate difficulty in chewing or swallowing, and should also be taken into account in this context. Thus, cardiac, pulmonary, gastrointestinal and neurological exams evaluate the diseases that contribute or cause weight loss.

In this population, the unintentional loss of weight can lead to a functional decrease in activities of daily life, greater hospital morbidity, increased risk of hip fractures in women and an increase in mortality in general. In addition, cachexia has been associated with negative effects such as increased infections, pressure ulcers and lack of response to medical treatments.

Regarding the diagnosis, a prospective study evaluated 101 patients (hospitalized and ambulatory) with an average age of 64 years and an unintentional weight loss of at least 5% in a period of six to twelve months. The initial evaluation included a complete medical history and a physical examination. After the initial evaluation, the aetiology of unintentional weight loss was established in 73 patients (72%). The organic disease was identified in 57 patients and 16 patients had a psychiatric diagnosis. More importantly, the 22 patients with malignancies had discrepant results in the initial evaluation. The most relevant parameters at the time of diagnosis were C-reactive protein, hemoglobin levels, the plasma presence of lactate dehydrogenase and the serum concentration of albumin. In summary, the authors concluded that if the results of the baseline tests are normal, no further studies are necessary and a close observation of three to six months was carried out.

If a treatment is required, the intervention of a multidisciplinary team is recommended: dentists, doctors, nutritionists, physiotherapists and psychologists, among others. The most common nutritional strategies to treat weight loss are dietary changes, environmental modifications, nutritional supplements, flavour enhancers and appetite stimulants.

Finally, there are several medications to stimulate appetite, but it hasn’t been shown that any of them reduce mortality in elderly patients with involuntary weight loss. Megestrol (Megace) has been shown to improve appetite and increase weight in patients with cancer and cachexia. However, it has side effects, so it is not appropriate for all patients. Mirtazapine (Remeron) is a serotonin antagonist to treat depression. 12% of patients who take this drug report weight gain. Dronabinol (Marinol) and growth hormone have been studied in pilot trials with variable results with respect to weight gain. Thus, Dronabinol has been associated with significant adverse effects and growth hormone with an increase in mortality.